1. Field of the Invention
The present invention relates generally to image formation devices, and in particular to a coupling retraction mechanism for a color electrophotographic printer. Specifically, the present invention discloses an Oldham coupler for transferring rotary power between two shafts in a developer unit of the image formation device including an input metal plate, a plastic star plate and an output metal plate.
2. Description of the Related Art
Oldham couplers have been employed for many years in drive systems of diverse machines for transferring torque or rotary power between two parallel but non-collinear and/or non-radially aligned rotating shafts. In the past, Oldham couplers with retraction splines have all the components made out of plastic. This leads to a weak design from the standpoint of the stiffness of the drive connections in the drive system. Since mono or color machines are sensitive to low frequency oscillations of the drive connections, the all-plastic components can cause banding in the range of 0.5 to 2 mm on a media sheet as the drive system oscillates which appear as light and dark bands on the printed media sheet.
Given the foregoing, there is a need for an improved Oldham coupler that possesses the requisite stiffness, is simple in construction and is relatively easy to manufacture.